1. Field of the Invention
The invention resides in the field of limb supports for surgical procedures and more particularly relates to supports adjustable over a selected range of positions.
2. Description of the Prior Art
Adjustable supports for immobilizing limbs during surgical procedures, whether the surgery is performed on the limb or another part of the body near the limb, are known in the prior art. In particular there are positioning devices incorporating ratchet mechanisms which lock into place at preselected positions. Further U.S. Pat. No. 6,058,534, Navarro et al., discloses a support infinitely adjustable over a selected range using a compressed gas locking cylinder which may be secured or locked in a desired position and then unlocked to reposition the support.
While the locking cylinder provides a level of assistance, the support must none the less be manually lifted or lowered by the surgeon or an assistant to reposition the limb during surgery.
In contrast, the present invention eliminates the need for such manual manipulation by providing an externally powered limb support actuator which may be controlled by the surgeon or an assistant without interruption of the surgical procedure to make any required adjustments.
The invention may be summarized as a limb, i.e., arm or leg support, arranged to hold and immobilize the limb in a variable selected position during a surgical procedure. The device consists of a base attachable to a surgical table, a post attachable by a clamp for example; a support arm pivotally attached to the base; and an extendable and retractable externally powered position actuator pivotally mounted to both the support arm and the base. The actuator may comprise an electrically powered linear actuator having a motor and screw assembly to provide displacement or a compressed air or hydraulic actuator. A control system is provided to extend or retract the integral operating arm which is driven by one of the above named power sources and may be in the form of push buttons mounted on the actuator or hand held and remotely connected by wire or a foot switch or the like. An appropriate limb holding device attached to the support rod, a surgical boot for example, completes the invention.
As the device is powered by an external source, repositioning the limb is independent of gravity and the lifting force, which must be supplied by the operator in prior art devices. Further, minute changes of position may be accomplished without the surgeon discontinuing the operating procedure, and without any likelihood of mispositioning by an assistant or the surgeon themselves as might happen if they are required to leave the operating site to perform an adjustment. Additionally, the danger of slippage resulting in potential injury to a patient is eliminated since a positive control act must be performed to reposition the support arm. This can only take place at the operating speed of the actuator.
These and other features and advantages of the invention will become more clear from the description of the preferred embodiment and drawings which follows.